Manufacture of creped paper



Feb. 17, 1953 STEVENSON 2,628,656 I MANUFACTURE OF CREPED PAPER Filed July 29, 1950 3 Sheets-Sheet l INVENTOR ALLAN B. .STEVENSTON FIG.

ATTORNEY Feb. 17, 1953 A. B. STEVENSON 2,628,656

MANUFACTURE OF CREPED PAPER Filed July 29, 1950 3 Sheets-Sheet 2 FIG. 4. FIG- 3.

FIG. 6. FIG. 5.

INVENTOR ALLAN B. STEVENSON ATTORNEY Patented Feb. 17, 1953 MANUFACTURE OF CREPED PAPER Allan B. Stevenson, Attleboro, Mass., assignor to American Reenforced Paper Company, Attleboro, Mass., a corporation of Massachusetts 7 Application July 29, 1950, Serial No. 176,679

2 Claims. 1

This invention relates to the creping of webs of paper and the like and has for its objectives to provide a new method of creping, new apparatus therefor, and also a creped product having novel characteristics.

In the longitudinal creping of paper to impart transverse stretchability, difficulty is encountered in the use of conventional equipment on light-weight papers, due in part to their inadequate strength when wetted. In accordance with the preferred practice of the present invention, this difficulty is obviated by drawing the paper through one or more apertured dies having funnelor bell-shaped entrances which ease the passage of the paper through the die. Preferably the successive dies have throats of successively diminishing sizes to contract the paper gradually from a wide fiat sheet to a compacted, rope-like form having a cross-sectional diameter which is a small fraction of the original width of the flat sheet. The paper is then squeezed between rolls after which it is fanned out to its creped dimension widthwise and finally dried. In practice it has been found that transverse stretchability of the order of several hundred per cent, if desired, may be imparted to comparatively light-weight paper.

The paper produced by the method and apparatus of the present invention is believed novel and superior in its creping configurations to paper creped according to conventional practices, in thatithas a measure of stretchability in virtually all directions.

Paper made in accordance with the present invention is useful particularly in the manufacture of adhesive laminated papers which may be employed for wrapping and packaging, or for box stay tapes such as are described in the U. S. Newkirk Patent No. 2,089,405 and the Smith Patent No. 2,026,194. The virtually universal stretchability permits the paper thus reenforced to be tensioned in many directions without breaking the paper fibers.

In the drawings:

Fig. l is a side elevation, partially diagrammatic, showing the preferred embodiment of the creping machine.

Fig. 2 is a plan view thereof.

Fig. 3 is a vertical section through the first trumpet.

Fig. 4 is a front elevation of the first trumpet.

Fig. 5 is a vertical section through the second trumpet.

Fig. 6 is a front elevation thereof.

Fig. 7 is a plan view or a sheet of creped paper,

2 j. showing the sections with difierent creasing, and

Fig. 8 is an edge view of the paper.

The machine of Figs. 1 and 2 includes a frame 3| having supports 32 for an arbor 33 carrying a roll of paper 33a to be creped. The paper is unrolled and drawn under rollers 34, 35, roller 34 being within tank 2| and immersed in water 2|a preferably containing a small amount of a wetting agent. Roller 35 is just above the water level, as shown. The paper is then drawn be tween the squeeze rolls 36, 31, adjustable as shown, to remove excess water. Roll 36 is power driven by the vari-speed drive unit 38 to which it is coupled by belt 39, and roll 31 is pressed against roll 36- by springs 40 which urge the bearing bracket 4| downwardly on the bolts 42.

After the paper passes between the rolls 36, 31, and over roll 31, it passes to approach roll 50, also rotatably mounted on the stand 31. As the paper is brought up and over roll 50, it is properly aligned for horizontal advance over the frame toward dies 22, 23, being drawn in that direction by unit 24 comprising power driven squeeze rolls 5|, 52. The bottom roll 5| is coupled with the vari-speed unit 38, by belt 53 and chain 54. Roll 52 is adjustably pressed downwardly against roll 51 by springs in the same manner as roll 31 is pressed against roll 36.

The paper i is drawn through die 22, thence through the second die 23 with a slightly smaller orifice. The use of successive orifices of diminishing size is desirable to facilitate contraction of the web to rope-like form of a diameter which is only a small fraction of the flat width of the paper.

The die 22 should be located a sufficient distance from roll 50 to prevent tearing of the paper by converging it too sharply. The minimum distance between roll 50 and die 22 will depend upon such factors as the width of the paper, its type, Weight, water content and the size and shape of the die 22 through which the paper is first drawn. The second die 23 should be disposed far enough from die 22 to permit any air, which may have become entrapped during the converging of the paper through die 22, to leak out and thus avoid bursting of the paper by subsequent compression of entrapped air.

The dies may be of the shape shown in Figs. 5 and 6, although any funnel shape which will ease the paper into the orifice without tearing the paper or rupturing it, would serve. For a 12" width 30 1b. kraft, for example, a 1 /2" trumpet entrance diameter and P orifice works well; the second die may have a 1" entrance diameter, and

3 1%" orifice. The exits preferably should be slightly beveled, as shown at 22a, 23a, to assure against rupturing of the paper, although such beveling is not essential.

The squeeze rolls 52, in addition to providing the pull by which the paper I is drawn through the dies 22, 23, affect the final crepe pattern, depending upon their distance from the exit of the second die 23. A finer creping is obtained as the distance is decreased. In the example given, to 2" is a fair range.

After the paper leaves the squeeze rolls 5|, 52, it passes over spreader 25 which is convexed to aid in spreading the paper to its full creped width without tensioning it laterally to remove creasing. From the spreader, the paper passes around lower drying drums 29 and upper drums 30, alternating between the two sets of drums as shown. The blanket 70 trained around guide rolls 12 serves to press the paper into peripheral contact with the lower set of drums, and a similar blanket l4 trained around rolls [6 presses the p per against the upper series of drums. The d ums are heated, as is conventional in the paper industry.

After being dried, the paper is wound up at 27.

Figs. 7 and 8 illustrate diagrammatically paper that has been creped by the method and machine described above. The converging folds la later contracted and compressed in passing through the dies and between the squeeze rolls 24 result in an arrangement of paper creases to impart a sort of herring-bone appearance with the creases extending at various inclinations lengthwise of the paper, but in the aggregate extending preponderantly lengthwise or in the machine direction of the paper so that the paper has a high degree of transverse stretchability when tensioned transversely as on the line BB, Fig. 7. The crepings are arranged in sections, of which four are shown, designated 10, H, H and I3. The crease lines, in each section run preponderantly in the same direction at an inclination to the length of the paper and with the crease lines in one section disposed at an acute angle relative to the crease lines in the next adjacent section. The average directions of the crepe lines in the sections is indicated by the dash-dot lines A-A, AA', A"A", A"-A". Because of this relative inclination of the crepe lines, the paper has stretchability in many directions other than purely transverse.

4 Thus, stretchability is present as the paper is tensioned along such diverse directions as BB and B"B". Indeed there is some measure of stretchability even when tensioned along a line nearly parallel with the longitudinal axis of the Web.

I claim:

1. Apparatus for creping a web of material to impart transverse stretchability, comprising a plurality of apertured dies through which the paper is drawn in succession, said dies havin openings which are substantially circular in cross section and are substantially smaller than the fiat width of the web and one of said dies having one opening which is smaller than the opening in another of said dies which precedes it, and means for drawing the web successively through the dies to compact the web laterally.

2. The method of making creped sheet material which consists in wetting a Web of the material, forming the wetted web into a plurality of longitudinal folds extending continuously in converging directions from an area of the'web 0ccupying substantially its full unfolded width to a narrowly contracted area thereof, while the web is unsupported, thereafter further compacting the web laterally and subsequently pressing the compacted web to impose crepings in the web, and thereafter spreading the web to a width substantially greater than said contracted width and substantially less than said full unfolded width to substantially remove said converging folds while avoiding such tensioning of the web laterally as would remove the crepings, whereby the crepings are formed at various inclinations lengthwise of the web to impart stretchability to the web in various directions.

ALLAN B. STEVENSON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,196,888 Scherf Sept. 5, 1916 2,019,903 Heitmann Nov. 5, 1935 2,094,081 Platt Sept. 28, 1937 2,153,374 Kantor Apr. 4, 1939 2,176,019 Cohoe Oct. 10, 1939 2,494,723 Rowe Jan. 17, 1950 

